The Emptiness Inside
by Callicokitten
Summary: "We are one now, little brother." Sebastian and Jace are now one person. Sebastian's taking control from Jace and is determined to ruin Jace's life; starting with Alec. Jalec, Malec and dark themes.
1. Stardust

**AN: **I haven't read the books in forever so sorry if I get anything wrong or if someone's OOC. This story kicks off a few minutes after City of Fallen Angels ends and takes the idea that Sebastian and Jace _literally _become one, like a split personality thing. Also I love Malec. But I didn't like Alec's sudden loss of feelings for Jace. So hum.

(also never stalk the Jalec tag on tumblr.) Title is from the Gregory and the Hawk song Boats & Birds

"_We are one now, little brother, you and I. We are one."_

Jace blacked out, that voice echoing through the darkness and when he awoke he was alone on the rooftop and Sebastian's body lay limp where it had almost been. His stomach turning, he leant in and pressed two fingers to his brother's neck. He almost sobbed with joy when he didn't feel a pulse.

When he got down to the lobby he found it empty but for Clary. She smiled as he walked towards her, "You look kind of pale." She remarked when he reached her.

He flashed her a winning smile, "Well it's not every day one is involved in a plot to resurrect a being of pure evil. Or possessed for that matter."

She looked convinced and took his hand, "Let's go, everyone else has already gone back to the Institute."

Jace nodded and swallowed, glancing back once as they left the building. He didn't understand how, but he could have sworn he heard a tut in his head when Clary took his hand.

Alec knew there was something wrong with Jace the minute he got back to the institute that day. He knew it the moment he saw his parabatai's eyes. When he'd asked Jace had brushed him off with a smile and a witty comment, but his hand had been shaking and Alec never missed anything about Jace.

And Jace knew it. So for almost two weeks now he'd been avoiding him. For almost two weeks he'd spent every waking moment with Clary or training and Alec was seemingly the only one worried. He'd asked Izzy if she thought something was wrong, he'd asked Clary too, and both of them had told him he was just being paranoid.

But Alec knew there was something.

He saw it in the way Jace occasionally cocked his head as if he were listening to a voice that wasn't there. And the way Jace ran his hands through his hair nervously, and chewed his lip and bit his nails when he thought no one was listening. But mostly he knew it by the way he'd hear Jace talking in his sleep some nights when he snuck passed Jace's room on his way back from Magnus'. At least he thought Jace was talking in his sleep. If he wasn't he was holding long conversations with himself, which was slightly more worrying.

Magnus was getting annoyed by Alec's constant worrying. He'd dismissed Alec's concerns by saying that anyone would be more than a little shaken by what had happened to Jace. It was understandable. But still...

"Alexander, what is the point in coming over here if you're just going to sit there and brood over your _brother_." Magnus said, sulkily from somewhere behind Alec. Alec pretended not to notice the emphasis on the word 'brother'.

"I'm sorry," he said, turning and smiling at the warlock who was standing with his arms crossed. "It's just he's my parabatai, I can _feel _there's something wrong."

Magnus smiled apologetically and came and sat beside Alec on the couch. "I know, I know, I'm sorry." He said, wrapping his long arms around Alec. "I still get jealous though."

Alec blushed slightly and Magnus chuckled, running a finger over Alec's cheekbone. "You're cute when you blush."

Alec smiled and knew he'd be sneaking back to the Institute in the small hours of the morning _again_. He had to stop doing this, he thought, he had training to do and then Jace to worry about and- oh. He stopped thinking when Magnus' lips met his own.

As he predicted Alec was again sneaking back home at gone 4 in the morning. The only one still up was Church who looked at him disapprovingly as he crept passed. He paused in front of Jace's door and again heard a low murmuring.

He was about to walk passed and crawl into bed when the voice from Jace's room got louder.

"What the _fuck_? No. Get the hell out!" Jace was saying, sounding enraged. "You _can't _be here!" then he laughed and said, "Oh, shut up."

Alec was understandably concerned and for a few moments he stood frozen outside his parabatai's door. He was just about to leave when the door swung open and he was met by a smirking Jace. "Evening Alexander, returning late from a night of wild warlock escapades, are we?"

"I-no...Jace!" Alec spluttered as Jace smiled wider.

"Then why, pray tell, are you lurking outside my bedroom door?"

"I..uh," Alec stammered. Now he was face to face with Jace all his well rehearsed speeches had dissolved. So he settled for saying, "I heard you mumbling in your sleep."

Jace's smile faltered so Alec added, "Are you okay? You've been weird since the hotel thing."

Jace held the door open wider, "Well you may as well come in."

They sat facing each other on Jace's bed, as they had done so many times before; since they were kids. But this time there something different about it. Jace's posture was rigid and he was refusing to me Alec's eye, instead he seemed focused on a loose thread on his sheets.

"I've been thinking lately," Jace said eventually.

"I didn't know you could do that, Jace." Alec said before he could stop himself.

Jace swatted him playfully and then looked away again. "I was thinking about Idris; that night when I asked you to kiss me and you didn't."

Alec flushed at the memory. It had been so tempting. He could have _just..._but he knew what Jace was doing and he knew that Jace hadn't wanted it. He looked up at Jace who was watching him closely through his golden eyes. "What about it?" he asked, trying his best not to let his voice shake.

"Why didn't you?" Jace asked quickly.

Alec blinked. "You-you..." he stammered. "You didn't...You were right." He said finally. "I didn't love you, really."

Jace smiled slowly, a slow predatory smile that would have looked more at home on a shark. "Is that true, though Alec?" Jace asked in a purr.

Alec's eyes widened as Jace drew closer. "Jace-" he began.

"Alec." Jace said, still smiling.

"Y-You know it's true. I'm with Magnus. And you're with Clary."

Jace nodded, "I know. But come on, you can't tell me you aren't the least bit _curious?_"

"You're drunk-" Alec said, backing away but Jace was too fast. He leant forwards and pressed his lips to Alec's.

Alec should have pushed him away. They were both taken. This was wrong. _So wrong._ But he didn't. He kissed back. And it was everything he had imagined.

Jace's kisses were like fire and as he drew Alec closer to him he began running his hands over Alec's body, leaving a burning trail behind. Alec shivered and Jace smirked and deepened the kiss, pushing Alec backwards and clambering on top of him.

Alec closed his eyes and let himself get lost in Jace. Jace his brother. Jace his best friend. Jace his first love. Jace his parabatai. Jace his soul mate. _JaceJaceJaceJace._

When Jace pulled away Alec's head was spinning.

Jace smiled softly and ran a hand across Alec's cheek. "Sorry Alec, but I couldn't stop myself."

Alec sat up slowly. His mind was a hurricane, Jace_ kissed _me._ Jace _kissed _me. _**Jace kissed me.** His heart was pounding. "Wh-Why?" he stammered.

Jace looked almost sorrowful. "I...I just wanted to know what it was like. We can talk about this tomorrow, yeah?" he said, in an entirely un-Jace-like tone.

"Uh, yeah." Alec said, once his brain had processed what had been said to him.


	2. It Bubbles, Blisters, Burns My Palms

**AN: **angst ahoy! Chapter title is from Brother's Blood by Kevin Devine. Thanks for the reviews! Keep 'em coming? This story will be slow coming sorry guys! Please don't hesitate to give me a nudge if I take too long with updates though :)

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><p>Alec stumbled out of the room and behind Jace's eyes Sebastian smiled. He could feel his little brother screaming and raging from whatever corner of his- <em>their<em> brain he was currently locked up in.

"Oh, be quiet little brother. I didn't do anything your _brother_ didn't want me too." Sebastian muttered. Jace screeched in wordless anger and Sebastian chuckled. "You won't be able to do anything. If you tell him I'm in your head he'll think you're insane. Besides, I won't let you."

_This isn't fair_. Jace said, _why're you doing this to him?_

"Because the only other person you love that much happens to be my little sister. And she is, regrettably, the last remaining member of my family. I am not a monster, Jace."

Jace laughed. _Yeah, you're just a misunderstood body-stealing, murderer who's destroying an innocent Shadow Hunters life. _

Sebastian sniggered."Not my fault, Jace. Demon blood."

For a few moments Jace was quiet and then he said, _please, Sebastian. You don't understand._

"Don't understand what, little brother?" Sebastian snapped angrily. "I_ understand_ that you are with Clarissa. I _understand_ that he is with that awful warlock. And most of all I understand that he used to be in love with you, did you know he was breaking the law by doing that?"

_He wasn't in love with me._ Jace replied firmly.

Sebastian snorted.

The next day Jace couldn't find Alec anywhere. Isabelle said he'd gone to see Magnus but somehow Jace doubted that was true. He'd been about to go out to look for Alec when Clary had turned up with a DVD and her smile that he couldn't say no to. Sebastian gagged somewhere in his head. _Fucking Sebastian. _

He'd known something had been wrong since the hotel. But he hadn't worked out what it was until a week later when he'd heard Sebastian's voice very clearly in his head. At first he genuinely thought he was going insane. It happened to Shadow Hunters more often than people thought. It had felt as though there was something _inside _him. In his head, in his veins. Corrosive and destructive.

And then Sebastian had taken control. Jace was there. Inside. He could see what was happening but he had no control over it.

The first few nights Sebastian had just wandered around. Then he'd targeted Alec. And _by the Angel,_ if Jace could have he would have torn Sebastian apart piece by piece and then reassembled him only to do it all over again. There was part of him, the part that constantly thought _Clary, Clary, Clary that_ was grateful that Sebastian hadn't targeted Clary. That part of him made him sick.

Alec was his parabatai. His brother. His best friend. The first person he'd ever truly cared about.

_Do you really care about him? _Sebastian sniggered from deep within his mind. _I mean how much time do you even spend with him anymore?_

"Shut _up,_" Jace growled making Clary jump. _Dammit,_ Jace cursed himself as Sebastian laughed.

"Jace? What?" she asked completely baffled.

"Nothing, sorry. I said I meet Alec later. He's having sparkly warlock shaped problems apparently." Jace lied quickly.

Clary frowned at him; she was getting annoyingly good at seeing through his lies. But Jace left before she could ask any further questions. _Great, _he thought to himself. _Now my girlfriend thinks I'm batshit._

Sebastian laughed and drawled, _Good. Maybe she'll find someone half decent. _

Jace stuffed his fingers in his ears and imagined that helped.

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><p>It was almost midnight when Magnus heard a knock at his door. He glanced at Chairman Meow who gave him a look that clearly said; <em>well it's hardly going to be for me, is it? <em>He sighed and paused the rerun of Glee he was watching before shuffling over to the front door.

When he opened it he blinked in surprise, "Alexander?"

The Shadow Hunter stood, shivering slightly on his doorstep. "Sorry," he mumbled looking down at his feet. "I just need to talk to you."

Magnus opened the door a little wider, "Come on then." He said to Alec, taking his hand as they walked into the sitting room. He could tell something was wrong, very wrong. He hadn't seen Alec this nervous since the first time they'd met.

"What's wrong?" he asked, immediately. When Alec finally met his eyes Magnus knew.

"Jace." Magnus growled quietly. He'd always known that Alec wasn't entirely over Jace; he'd always known that if Jace had shown even the slightest bit of interest they would be over. It wasn't that Alec didn't love Magnus, Magnus knew he did. It was that Alec and Jace were parabatai, their souls and destinies intertwined.

Alec looked at Magnus, wide eyed. "I...I'm sorry." He finished lamely.

Magnus looked at Alec for a very long time, studying the Shadow Hunter. His deep blue eyes, his pale skin, his soft black hair. He was beautiful but so, _so _broken. Magnus had had enough of broken boys so he made the hardest decision he'd ever had to make. "Alec, I want you to leave."

Alec gaped at him, "Wh-What? Why?"

Magnus crossed his arms. "Do you think this is fair, Alexander? I love more than I ever believed I could, in a way I thought I had forgotten. Feelings grow duller the longer you're alive but with you it felt like the first time again. But you treat me like a backup plan."

"N-no! That's not-" Alec spluttered tearfully.

Magnus took a deep breath and steeled himself. He knew he was being cruel but it was something he needed to do, for both of them. Then maybe Alec could move on from Jace. Or Magnus could move on from Alec. But as he watched Alec tremble and try to hold back tears he knew that he'd never move on from the Shadow Hunter.

"I _love _you!" Alec begged. "Please, don't do this."

"I'm sorry, Alec." Magnus said looking away.

"You can't do this..." Alec whispered. "Magnus _please."_

Magnus stood up and walked back to the front door. He opened it and said, "When you grow up and work out what you want _then_ come back."

When Alec finally left Magnus locked the door and curled up and cried.

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><p>Jace felt Sebastian creeping forwards in his mind almost as soon as he, <em>they<em>, spotted Alec. He tried to fight him off but Sebastian easily took control and Jace felt the familiar feeling of helplessness and the acid-burn throughout his veins. He tried to cry out but it was too late and Sebastian laughed.

Alec turned to him and his eyes were red with tears. "Jace?"

Jace wanted to scream, _no, run Alec. _But Sebastian didn't let him. "Alec, what's wrong?" he asked calmly.

Alec sniffed as Jace sat down beside him, concern evident in his golden eyes. "Magnus...he broke up with me." Even as he said it Alec cursed himself for being so _weak. _Magnus Bane had reduced him to a quivering mess of tears. But he had loved Magnus, he really, _really _had.

Jace put an arm around his shoulder and Alec could feel him shaking with anger. "That _fucking _Warlock. "

"Don't hurt him," Alec mumbled.

"Fine," Jace growled. "I won't hurt him...yet anyway." He sighed and ran a hand through Alec's hair and Alec was too tired to pull away. For a few moments they sat in silence and then Jace spoke again, "You know, maybe it's for the best. You and Magnus I mean. I mean think about it; he's an ancient Warlock, he's been with hundreds of people and I bet he would have dumped you the minute you weren't young and pretty anymore."

Alec wanted to say _Magnus isn't like that. He wouldn't!_ But Jace was watching him like he had done the night before so Alec just nodded and closed his eyes.


	3. Atmosphere

**AN: **I'm going to warn you guys now, this fic is going to get _dark._ And I mean _**dark.**_Like dark. Darker then dark. May be a slight overreaction. But. Dark. Okay? Also, I've decided to start referring Sebastian!Jace as Sebastian when it's his pov more. So it may get confusing, ah well.

Thanks a lot for all the reviews! And the songs Alec listens to are My Body Is A Cageby Arcade Fire and Atmosphere by Joy Division, which is also where the title comes from.

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><p><em>Jace was running. His veins were pumping battery acid and his lungs were screaming. <em>

_He tripped, fell, bled. And rolled over, groaning in pain. Sebastian stood over him laughing, a laugh that grated at his ears and sent shivers down his spine. _

"_You can't escape me, little brother," he said, leaning down until he sat on Jace's chest. "We're one now, you and I, forever."_

Jace woke up with a jolt, Sebastian's laughter echoing through his head. His head was pounding and his legs ached, as though he really had been running all night. He sat up and tugged at his hair in frustration just as there was a knock at his door. "Who is it?" he called, his voice shaking slightly.

It was Izzy, frowning at him worriedly. "Clary wants you to call her. She's called me about forty times, turn your phone on!"

"Shit, Iz. Sorry," Jace mumbled, reaching for the mobile on his bedside table. He turned it on to see ten missed calls from Clary. He also saw that it was almost 4pm.

He groaned, "Why didn't anyone wake me up?"

"We tried, by the Angel, we tried." Izzy said, smiling slightly. "You were dead to the world, late night?"

"I have no idea," Jace said, pinching the bridge of his nose in pain.

Izzy's smile vanished and her expression turned serious. "Jace, what's going on with you?"

"Isabelle..."

"No lies, Jonathon Lightwood," she said sternly and Jace was suddenly struck by how much Isabelle could sound like Maryse when she wanted to. "You tell me right now. Everyone's worried, me, Clary, mom, dad, Alec, even Simon's asked a few times! So you tell me right now."

_Sebastian keeps taking over my body, _Jace wanted to scream. _Half the time I don't know what I'm doing. I can't control it and he keeps hurting Alec._

Oh Gods, Alec.

"Where's Alec?" he snapped, ignoring her question.

She sighed. "He won't come out of his room. I think him and Magnus have been fighting."

It hit him in a flash. _"Magnus...he broke up with me."_

Sebastian had found Alec, whispered to him that Magnus wasn't worth his time. Magnus would only love him while he was pretty; he only liked Alec's looks. He only likes you because you look like one of his dead boyfriends, Will, was it? He'd said that Shadow Hunters shouldn't date Downworlders anyway; Shadow Hunters were so much better than that. Alec could do better. And Alec had just sat there and listened, _stupid. _

"We'll talk later, Izzy. I promise." Jace said, bolting out of his room.

He ran up to Alec's door and knocked. "Alec? Come on, Alec. Open up."

Alec didn't and Jace pressed his ear to the door. He could hear a melancholy song faintly through the wood. "_I'm standing on a stage, Of fear and self-doubt, It's a hollow play, But they'll clap anyway," _the singer crooned.

_Ugh,_ Sebastian murmured. _What a drama queen._

"Alec, please open up. Talk to me?" Eventually though he accepted that his Parabatai wasn't going to open the door and he returned sullenly to his room to dress and headed over to Clary's.

When he knocked on the door she answered with her hands on her hips and her green eyes hard, "What the fuck, Jace? You were supposed to meet me over two hours ago. I called you a million times! I thought something bad had happened! Then Izzy told me you were just sleeping, so what the hell?"

"Clary, I'm sorry. I don't...I had a late night. Hunting demons, you know." He said, flashing her his best smile.

She was unconvinced and she sighed. "Jace, do you think I'm stupid? You may be a very talented liar but I can tell when you do now." Then she reached out and brushed a hand against his cheek. "What's going on with you?" she sounded desperate and tired.

"Izzy's worried. And Alec, Alec's been worried for a long time."

_It's Sebastian, he's-_ but the words caught and died in his throat.

_I told you, little brother. You can't tell anyone about our little arrangement. _He could almost hear Sebastian's smirk.

He looked at Clary, so worried and desperate and beautiful and lied. "Look, I'm just having a hard time dealing with what's happened lately. I've been having trouble sleeping. But I'm getting better, I promise you Clary, do you trust me?" he said, cupping her face gently.

She stared at him for a long time before saying, "Okay, I trust you, Jace." And leaning in to kiss him.

When she did he couldn't help comparing her to Alec. He pushed her away gently and grinned, "So let's go see that dorky film you wanted to, hm? I'm sure we can't have missed all of the showings."

She smiled and nodded and took his hand. "And by the way it isn't dorky." She added, cuffing him gently.

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><p>Alec shivered in the cold night air and turned his coat collar up against the wind. He had spent the whole day thinking about Magnus and Jace, Jace and Magnus. His boyfriend and his brother. <em>Ex<em> boyfriend, now. Alec's heart clenched painfully at that thought. _It couldn't be over. _Magnus had said it would be forever. Well, for as long as Alec lived anyway. Magnus had thought he was special. So it couldn't be over. Alec wouldn't let it be.

If he lost Magnus who did he have? Isabelle? But Izzy had Simon. Jace? _Oh, _Jace. Jace had kissed him. Held him. But Jace was in love with Clary and Alec's head hurt whenever he tried to work out what his foster brother had been thinking that night.

When he reached Magnus' apartment he knocked loudly and upon receiving no answer he let himself in, thankfully Magnus hadn't changed the locks.

Magnus was sitting on the couch smoking and reading a book. Alec had never seen him smoking before.

"What are you doing here, Alexander?" he asked, without looking up. His voice was dull and cold.

Alec took a deep breath. "Don't do this, Magnus. Don't break up with me." He said his voice steady. "I don't wanna lose you."

Magnus shut the book and looked up at Alec and the Shadow Hunter was shocked to see that Magnus' eyes were full of tears. "It's not that simple though, is it Alec?" the warlock said and for a moment Alec forgot that Magnus was ancient because right then he sounded like a scared teenager.

Alec felt tears beginning to sting his eyes. "Is this really what you want, Mag?"

Magnus shook his head, "No. No, I don't. But you love someone else, Alec. And I'm done with being the backup choice." He said, bitterly.

Alec looked down at his shoes and sniffed. "I don't..." he mumbled.

Magnus stood up and strode over to Alec. "Look me in the eyes and tell me you don't love Jace." He snapped, crossing his arms angrily.

Alec slowly met Magnus' cat eyes. "I-I don't...I don't love..." he looked away ashamed and Magnus shook his head. "What's that got to do with us?" Alec asked in a very small voice. "You knew I was from the start. But I love you too."

Magnus smiled very sadly, "Oh, Alec. It has _everything _to do with us. You can't leave him, can you?"

"It's not that easy..." Alec said, as the tears began falling. "I've tried, he won't...I can't stop _thinking_ about him."

"Well then you've made your decision." Magnus said sadly, reaching out to stroke Alec's cheek. "I can't sit here and watch you destroy yourself for him. I can't stand it, Alexander."

Alec flinched away from the touch. "_Fine_ then!" he snapped. "Don't touch me!"

Magnus backed away, "Alec..."

"Just leave me alone!" He cried, turning and storming out of the apartment leaving Magnus staring bewildered-arm still raised- after him.

When Alec got back to his room there was someone sitting on his bed. "J-Jace?" he managed.

Behind Jace's eyes Sebastian smiled and Jace wanted to scream. "Alec, what's wrong?"

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><p>Sebastian had brought two bottles of vodka and Jace watched, powerlessly as he sat and encouraged Alec to drink them both. "Its okay, it's okay," he soothed, running a gentle hand through Alec's hair. "That Warlock didn't deserve you. You're better off without him."<p>

"'S your fault," Alec mumbled, standing up unsteadily and clicking his music player on. The song playing was so _Alec _and Jace felt Sebastian's rumble of annoyance. Alec stumbled back to the bed and lay back, looking up at Jace.

_Walk in silence,  
>Don't walk away, in silence.<br>See the danger,  
>Always danger,<br>Endless talking,  
>Life rebuilding,<br>Don't walk away._

"I _hate _you," Alec said and Jace felt a pang of regret. Sebastian meanwhile smiled and then Alec leaned up quickly and kissed Jace on the cheek. "You ruined my life."

_Oh, this is going to be such fun, little brother. _Sebastian cackled before leaning down, over Alec. "You don't really hate me," he said.

"Wish I did," Alec murmured, reaching up and touching Jace's cheek.

Sebastian leant down and kissed Alec, soft and chaste over and over again. "Do you ever want to hurt yourself?" he asked, lips pressed to Alec's throat. Jace trembled, _please stop this Sebastian. __**Please.**_

"Yes," Alec half sobbed. "All the time." His eye fluttered shut when Sebastian bit down on Alec's throat gently.

"Me too," Sebastian said quietly as he licked the skin he'd just bitten into. Alec's hands came up and clutched at Jace's back, his fingers grasping at Jace's t-shirt.

_Sebastian, you've done enough. _Jace begged.

Sebastian smirked and leant up to look Alec in the eye. His eyes were red rimmed from crying and for some reason that made them look startlingly blue. Sebastian ran his fingers across the red mark he'd left on Alec's neck and Jace swore he heard Sebastian murmur, _mine. _

"Love you, Jace." Alec's voice was a whisper and as soon as he'd said it he shut his eyes and bit his lip. "S-Sorry..." he mumbled.

Sebastian was still caressing Alec's throat and Jace's heart was breaking. _Please, Sebastian. Don't touch him again._

"Me too," Sebastian murmured before leaning down and kissing Alec again. Alec's mouth tasted like vodka and their tongues touched. Alec couldn't breathe, didn't want to anyway.

Sebastian rolled their hips and Alec moaned, low and needy. And Jace wished he was dead.

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><p>Jace woke up in Alec's room, in Alec's bed, thanking the Angel it hadn't gone any further then kissing and touching last night. He retched at the thought and stood up, breathing deeply. Alec was still asleep, chest rising and falling and covered in the deep yellow and purple bruises Sebastian had left with his mouth. <em>His <em>mouth.

Jace's mouth still tasted like vodka.

He padded silently down to the kitchen and rinsed his mouth out with cold water. It was 5am. Too early for anyone else to be up and Jace was glad. He didn't think he couldn't handle any human interaction after _that. _He made himself some breakfast and as he ate he kept expecting to hear a sarcastic remark from Sebastian, but he didn't. Sebastian wasn't gone; he could still feel him like an insect clicking across his brain.

He had to get Sebastian away from Alec. _Love you, Jace. _Those words had been so broken, so desperate. Jace growled and ran a hand through his hair in frustration. And then he had an idea.

If he couldn't get rid of Sebastian he could get rid of himself. He could leave. Run away, far away where Sebastian wouldn't be able to hurt Alec or anyone.

He ran up to his room and packed a bag before he could change his mind.

He got several trains and buses and by nightfall he finds himself just outside Washington. He found himself a cheap motel room and decided he'd get a plane somewhere the next day, then exhausted he fell asleep.

He woke up in his bedroom and fought the urge to scream.

_Don't try and run away, little brother, _Sebastian said quietly. _We have so much left to do._


	4. Raw, Bleeding Bait

**AN: **grab a flashlight kiddies this chapter's dark! Seriously. Also short. Sorry. Thanks a lot for the reviews; seriously, you guys are awesome. Also, I now have a beta :D Yoursforalleternity who is made of awesome.

Title from the beautiful song Luca by Brand New which I wrote this chapter to.

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><p>The next few days were like a waking nightmare. Sebastian was getting stronger. Jace would wake up every morning tangled in Alec's bed, his parabatai would be covered in bruises and bite marks and Jace's head would spin. Alec mumbled in his sleep and tossed and turned and whimpered. His dark hair damp with sweat, his skin pale.<p>

_Isn't it beautiful, little brother, _Sebastian would drawl. _The contrast between his skin and his wounds. The purples and reds, the yellows, the greens. It's beautiful._ When Sebastian was in control he would run his hands along the marks he'd left on Alec's pale flesh as though fascinated. Jace shivered at the memories, Alec gasping and twisting beneath him in pain and Sebastian humming in pleasure. Jace was grateful that Sebastian hadn't done anything more than that to Alec, he didn't think he could live with it if that happened.

_When that happens, brother,_ Sebastian corrected.

Jace almost fell to his knees at that. _Why are you doing this, Sebastian? _

_I want to break you, brother. Shatter you into a million pieces._

Alec never said anything, but then what would he say? He watched Jace with Clary like he'd done before Magnus, but this time whenever Jace looked at him he'd turn away and Jace would catch a flash of a bruise or bite mark and his stomach would clench. And he didn't what to do or say to make his parabatai understand. Izzy and Clary knew something was wrong, very wrong. But they had both assumed that Alec was upset about Magnus and that Jace was upset because Alec was. But Jace knew that one day they'd realise something else was going on.

And that day came far too soon.

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><p>Izzy had been sparring with Clary in the training room and Jace had been sniggering from the sidelines mostly to annoy his foster sister. "Jace! If you don't have anything constructive to say can you <em>please <em>go bother Alec instead?" Izzy snarled.

Jace tried to ignore the stab of pain that shot through him at the mention of Alec's name, "And miss the sight of you and my girlfriend falling over every five minutes? Never."

Izzy strode over to him, jaw clenched and Clary, sensing trouble stepped between them swiftly. "Guys, don't do this." She said, breathlessly. "Why don't we all go have some lunch?"

Jace took her hand, _normal, normal, act normal._ "As long as Izzy isn't cooking." He said, dragging Clary out of the room. Izzy rolled her eyes and followed them to the kitchen. Alec was sat at the table nose buried in a book but Jace could tell by the empty look in his eyes he wasn't really reading.

He looked up as they entered, "Hey," he said, his voice quieter than usual. They greeted him and Jace sat down opposite as Izzy and Clary debated over the different pizza places that might deliver to the Institute. When they decided on one and ordered Clary left to go and fetch it, leaving Jace with Izzy and Alec. Izzy swung herself up onto the counter and Alec went back to his book but Jace noticed that he'd been on the same page for almost ten minutes.

Izzy broke the silence, "So Alec, are you back together with Magnus?" she asked and Jace looked up to find her eyeing Alec's neck.

Alec snapped the book shut. "No."

She frowned and leapt off the counter, coming over to Alec and brushing his hair back to expose the bite mark. "Then who did this, brother?" she asked, poking the mark playfully.

Alec looked up at Jace, eyes wide and blue. Jace's gut clenched and inside his head Sebastian growled happily.

"I-" Alec began but his voice died in his throat and Izzy smile vanished.

"Alec, who did it?" she repeated, her voice hard.

"I-I..." Alec tried again; his eyes were now darting around the room.

Jace wanted to leave, wanted to make a joke, _anything _to make this better. But he couldn't; Sebastian had him frozen.

"Alec," she prompted concern evident in her voice.

Alec stood up, "No one," he said entirely too quickly before bolting from the room. Jace sighed with relief and it wasn't lost on Izzy. She turned on him, eyes blazing with fury. "Did _you _do that to him?"

Jace felt his world implode and for a moment he let himself feel the crushing wave of despair that broke over him. _This is it, _Jace thought. _Sebastian's won. _He scoffed, "Isabelle, really." But it didn't sound like him at all and he knew that this was it. He stood up intending to leave but she advanced on him and he backed away involuntarily.

"You did, didn't you? You fucking _bastard!_" She snarled, "How could you!"

"Izzy, I didn't...I don't..." he stammered, he couldn't think straight, Sebastian's laughter was echoing through his head, clouding his thoughts.

Izzy lashed out at him again and again, "JACE LIGHTWOOD YOU BETTER TELL ME WHAT'S GOING ON RIGHT NOW!" she roared.

Jace looked at her long and hard and said, "Izzy, I didn't do it."

Izzy slapped him soundly round the face and Jace raised one hand to his stinging cheek. Izzy shook her head, at a loss for words and Clary chose that moment to walk into the kitchen with an armful of pizza. Her smile faded. "What's going on?" she asked, putting the pizzas down on the table.

_This'll be fun,_ Sebastian muttered gleefully.

Izzy turned to her with tears in her eyes, "Go on, Jace, tell her. Tell her what you've done!"

Clary's eyes widened, "Jace, what?"

Jace wanted to die. _That can be easily arranged, brother, _Sebastian said quietly.

"Nothing happened, Clary. Izzy's just mistaken." Jace said, ignoring Sebastian. He tried to move past her to leave but she crossed her arms and refused to move. "What is she talking about Jace?"

"The bite mark on Alec's neck," Izzy spat.

Clary's mouth fell open and her green eyes filled with tears, "_What?"_

"Clary, you can't believe this," Jace began but Clary shook her head.

"I can see it in your eyes, Jace," she said quietly.

"Clary I-" he began desperately but Clary looked away and Izzy put an arm around her and said, "Jace, you need to leave now."

Jace went up to the greenhouse and _screamed._

"Are you happy now, Sebastian?" he mumbled brokenly. "You've ruined everything."

Sebastian laughed and said in a voice that chilled Jace right to the core._ You think that's it, little brother? Oh no, our game isn't over yet._

* * *

><p>Alec's door was locked but Sebastian made quick work of it.<p>

Alec sat up as he came through the door, shutting it firmly behind him. "What happened?" Alec asked cautiously. His eyes were red rimmed and his hair was rumpled, as though he'd been running his hand through it in frustration.

Sebastian smiled, "Nothing, don't worry."

Alec sniffed and nodded, he was listening to more depressing music. "Okay. Okay, but we need to...we need to stop this, Jace." He said quietly to his sleeves.

_Yes, yes, Alec!_ Jace cried.

He felt a surge of anger from Sebastian and his smile vanished. "Why?" he asked icily.

Alec took a deep breath and refused to meet Sebastian's eyes. "It's not right, Jace," he said quickly. "You're with Clary, its wrong. It's wrong."

Sebastian strode across the room to the bed, his hand tightening on the handle of the dagger in his pocket. He sat down and roughly turned Alec's head so their eyes met. "Don't you love me, Alec?" he asked sternly.

Alec's breathing quickened and when he spoke his voice shook, "I do, Jace. You know I do..."

Sebastian nodded and kissed Alec pushing him backwards roughly, murmuring _you're going to love this little brother._

He pulled out the blade and Alec eyed it nervously, "Jace...?"

Sebastian leant up and bit down on Alec's neck, making him bit back a moan. "It'll be okay," Sebastian whispered, pressing the blade into Alec's forearm. Blood welled up around the metal blade and Alec gasped. Sebastian watched the blood seep across Alec's pale skin, _beautiful._

Jace felt ill as Sebastian made an identical cut on Alec's other arm and Alec said, "Oh, oh," high pitched and breathless. Sebastian cut through Alec's shirt and pressed the blade into the bare skin of Alec's chest, biting his neck as he did so. Alec shuddered, arched, whimpered and scrabbled at the sheets.

Then Sebastian raised the blade to his throat.

Alec's eyes flew open, "Jace," he mewled.

Sebastian smiled slowly, "You're all mine, Alexander Lightwood." He hissed, pressing the blade closer to Alec's throat.

Alec's eyes widened, "Jace, don't, _please."_ His words were jumbled with panic as he began to work out what was happening.

Sebastian undid Alec's jeans with the hand not holding the knife. _Watch and learn little brother. _

_Don't do this,_ Jace begged. _Please, Sebastian. __**Not this.**_

Sebastian didn't stop.

* * *

><p>Magnus was awoken by a pounding at the door; he rolled over and decided to ignore it. After all it <em>was <em>4am. But the Chairman had other ideas and he leapt onto Magnus and yowled loudly in his ear.

"Okay, okay, Jesus," he said, sitting up. "I'll answer the fucking door." Chairman Meow gave him a smug look and curled up in Magnus' recently vacated bed. The cat was snoring before Magnus had pulled on some clothes.

He opened the door to find Alec shivering in the night air. He was crying, his skin was pale and he was out of breath and trembling. "Alexander, what happened?" Magnus asked, stepping towards him and hugging immediately.

"J-Jace," Alec mumbled against Magnus' chest. Then his knees buckled and Magnus only barely managed to hold him up.

"It's okay, Alec," he said softly as he half dragged, half carried the Shadow Hunter into the living room. "I'm here, it's okay now."


	5. Even the Rosebush, Thrown into the Sea

**AN:** missing scene that I was convinced to put back in. Warnings for noncon so feel free to skip it. Title is from the translation of the song Alec sings.

* * *

><p>Jace's hands are everywhere and everywhere they go they <strong>hurt.<strong>

"Stop, stop, please," Alec mumbles desperately. But Jace doesn't stop and Alec can't get away.

Jace smiles, feral and sadistic. "You bleed so pretty," he says in raspy voice as he trails the knife along Alec's chest. There's pain again but this time no pleasure, no soothing voice in his ear and Alec mels, "Jace, **please.**" He knows deep down inside him that this is his fault, he could have left, should have left. This is his fault for letting Jace do what he wanted with him and his fault for not saying no.

"Jace..." there are tears in his eyes and Jace's pulling off his boxers and the knife is back at Alec's throat. He knows what's going to happen and for one brief moment he considers pushing himself upwards, into the blade. It would all be over in a gurgle and a rush of blood. Absurdly Alec thinks about the mess it would make, the sheets would be ruined. He thinks about what would happen to Jace and decides he won't do it.

But this can't be Jace, because Jace isn't like this, wouldn't do this. _Right?_

Jace sits back and sweeps his eyes across Alec's body and Alec feels like a slab of meat on a butchers counter. Jace smiles again and with the hand not holding the dagger he trails his hands along Alec's body, pausing at every bruise and cut and bite mark and pressing down on them. "I love you like this," he comments idly. "The colours of the bruises on your skin, the blood. You're like a canvas." His eyes meet Alec's, "**My **canvas."

And for a moment Alec's sure Jace's eyes are jet black but then the knife is pressing into the soft flesh under his eye and all coherent thoughts vanish. "Such a pretty shade of blue," Jace says.

The knife moves away and Jace smiles, "Now, I'm going to make you mine."

He bites down hard enough on Alec's shoulder the draw blood and pushes in. It burns and hurts and Alec cries out.

A hand wraps around Alec's throat and squeezes and Alec closes his eyes.

He's not sure why but a song walks into his head. The song his mother used to sing him and Izzy when they were young.

"_À la claire fontaine, M'en allant promener,"_ he whispers softly to himself. "_J'ai trouvé l'eau si belle Que je m'y suis baigné."_

Jace giggles and the knife slides across Alec's ribs. "Sing louder," he says, pressing the knife in to flesh.

"_Il y a longtemps que je t'aime, Jamais je ne t'oublierai_," Alec whimpers imagining the knife sliding in between his ribs. It would be easy, he thinks, like slicing through butter. "_Sous les feuilles d'un chêne,  
>Je me suis fait sécher."<em>

"_Sur la plus haute branche, Un rossignol chantait," _Maybe it would be better. Easier.

"You're pathetic," Jace whispers as tears Alec apart. "Pathetic and disgusting."

"_Chante rossignol, chante, Toi qui as le cœur gai,"_

"You really think I love you? You're just a game Alec," Jace is panting now and Alec's eyes are still closed.

"_Tu as le cœur à rire, Moi je l'ai à pleurer,"_

"Open your eyes," Jace commands and Alec does so and he doesn't see Jace Lightwood. He sees Jace Morgenstern. "I never loved you."

"_J'ai perdu mon amie, Sans l'avoir mérité," _Alec's voice breaks. This isn't Jace, this _can't_ be Jace.

Jace laughs. "You little _whore._ So desperate for my attention."

"_Pour un bouquet de roses, Que je lui refusai,"_

Jace finishes with a groan and pulls out, falling heavily on top of Alec, spent.

"_Je voudrais que la rose, Fût encore au rosier," _Alec continues. His whole body is shaking with revulsion.

"Shut up," Jace growls. He stands up and leaves without another word. Alec curls in to himself.

"_Et que le rosier meme, À la mer fût jeté." _He murmurs to the empty room.


	6. A Glimmer

**AN: **this one's pretty short, sorry! But it features bamfy!Magnus to make up for it and it said all I wanted it to say :) Thanks so much for all the feedback! I love you guys, really!

* * *

><p>"Are you happy now?" Jace whispered. "You've...Oh, god Sebastian...You..." His mouth tasted coppery, <em>like blood. <em>He couldn't say it. Saying it meant it happened.

He shuddered and wretched but his stomach was empty by now. Every time he closed his eyes he could see Alec, writhing in pain, begging him to stop. _Him. _He had done that. He had-

"Gods, Sebastian, talk to me!" he begged but his brother was silent. He choked back a sob. When he'd got control back he'd run until he physically couldn't run any further and had collapsed on legs that felt like they were made of lead.

"What am I supposed to do now?" he mumbled.

He felt Sebastian smirk and then his brother whispered, _I could take care of all this, you know. _

Jace stood up quickly, "No."

* * *

><p>Magnus ran a shaky hand through his hair as he watched Alec toss and turn in his sleep. He had healed Alec's physical wounds but he knew that wasn't even a quarter of the battle. Alec hadn't said a word since Magnus had let him in earlier that night and oh, <em>Gods <em>the blood. Magnus had lived a long time; he'd seen blood before, a _lot _of blood but _that? _That had been most sickening thing that Magnus had ever seen.

He'd sat here watching Alec sleep almost the whole night.

Magnus had wanted to make Jace's blood boil in his veins, to tear his head off and make him wish he'd never been born. And Magnus knew how to do that. He didn't care that killing a Shadowhunter would be a death sentence for him. Jace deserved and more. And yet...

Magnus didn't really believe Jace could have done this. The boy was an immature asshole but he loved Alec that much was clear. And he loved Clary. So why would he do _this_? He hadn't been himself since the possession incident, or so Alec said. Maybe he was still possessed. But that couldn't be true...could it?

His thoughts were interrupted when Alec mumbled under his breath. Just one word but it was enough to chill Magnus to the core. "_No,"_ Alec whimpered.

Then it became, "No, Jace, please _don't_!"

And Magnus was shaking him awake, "Alec, Alec, shh. It's okay, it's okay."

Alec's eyes flew open and filled with tears almost immediately, "M-Magnus?"

"Hey," Magnus said softly.

Alec's eyes widened and he bit his lip, "I'm sorry, Magnus. I'm sorry..." He began to cry and Magnus held him close and whispered comforting words into Alec's hair, all the while imagining twisting Jace's head off. Eventually Alec fell in to an uneasy sleep and Magnus stayed with him, running his hands through Alec's soft dark hair.

He only disentangled himself from the Shadowhunter when he heard a knock at the door. "Watch him," he said to Chairman Meow as he left the room. For once the cat obeyed and leapt up onto the bed to curl up beside Alec's head.

His heart sank slightly when he opened the door to find Isabelle and Clary standing nervously on his doorstep. "Please tell me Alec's with you," Izzy said, looking up at him pleadingly.

Magnus closed his eyes. He knew that last thing Alec would want was for his sister to see him like _that._ "He's asleep, Izzy," he said eventually.

Isabelle looked like she was about to cry with relief. "Is he okay?"

Magnus sighed. "He'll be okay."

Izzy nodded slowly, "Okay, I trust you." She said eventually.

Clary stepped forwards, "Magnus, please, we really need to talk to you. Can we come in?"

Magnus wanted to say no so he could crawl back in bed with Alec but he didn't. Instead he opened the door a little wider, "Come on then."

"It's about Jace," Clary said when Magnus had led them in to the flat. "We can't find him and he's been different since the thing with Lilith and Sebastian."

And that was it. It clicked.

* * *

><p>Jace wandered numbly through the darkened streets, he had no idea what time it was all he knew was that if he kept walking he'd stay awake and Sebastian wouldn't be able to take over. His feet throbbed and his head pounded dully but his mind was blissfully blank.<p>

_Got to keep going, _he thought to himself. _ Got to keep..._

He bit back a sob. _Oh, how the mighty have fallen, _Sebastian sniggered in his head.

Jace clamped his hands over his ears, no longer caring what anyone thought of him. He just wanted this to _stop. _He walked down a road he vaguely recognised and turned off it in to a small park. He passed a bench, wished he could stop, just a few minutes, _just a few minutes._

He stopped for a few seconds. _Just a little bit..._

Then a voice from behind made him almost leap out of his skin, "Hello, Jace."

Jace span around, dagger held aloft, golden eyes wide with fear. "Who's there?" he hissed in an undignified squeak.

Magnus Bane stood staring at him, yellow-green eyes ablaze with fury, fists clenched and sparking by his sides.

_Oh Gods, _thought Jace as he realised what must have happened. _I'm about to be killed by a glittery Warlock. _

"Magnus," he choked. "Magnus, I didn't-"

The Warlock cut him off with a wave of his hands, "Be quiet, Jace." He snapped. "I don't want to talk to you. I want to talk to your brother."

Jace wanted to cry. "You know," he mumbled as Sebastian hissed in his head. "You know..."

_Don't think you're safe just because the Warlock knows I'm here, _Sebastian spat.

"Come with me, Jace," Magnus said a little softer. "We'll get rid of him."

Inside his head Sebastian scoffed, _don't you for one second think this will be easy, little brother._


	7. Oblivion

**AN:** sorry it's been so long, thanks a lot for the reviews as always :) the end is in sight guys! Also, this fic is now being translated in to Italian :D :D :D CYBER COOKIES FOR ALL.

Also, yeah. Rewatching Supernatural. DOES IT SHOW?

* * *

><p>When Jace came to he found himself tied to a hard wooden chair in a darkened room. The ropes cut in to his wrists and when he shifted to look around a bolt of blinding pain shot through his neck. He groaned and looked around; there was a pentagram drawn on the floor in chalk surrounding the chair but apart from that the room was empty.<p>

What the hell had happened to him?

He took a deep breath, intending to begin the arduous task of wriggling out of the bonds but the door to the room swung open and light spilled in, momentarily blinding him.

"You're finally awake," Magnus said from the doorway, sounding relieved.

Jace blinked in the bright light, "What happened?"

"Sebastian," Magnus said looking at Jace worriedly. "You don't remember?"

Jace shook his head. He remembered following Magnus out of the park, he remembered Sebastian laughing and that was it. "I don't remember anything."

"Where am I?" Jace asked, looking around again.

"You're at my apartment."

"You have a dungeon in your apartment?" Jace started to ask but Magnus shot him a devilish look and he petered off. "Of course you have a dungeon in your apartment..."

Magnus frowned and bent down to examine the pentagram on the floor. "What is that thing?" Jace asked.

"A demon trap; if someone is possessed it keeps the demon, or in this case Sebastian, subdued. It's something mundanes use."

Jace eyed the chalk circle doubtfully. It was a _chalk _drawing. How defensive could that be? He watched as Magnus traced the circle's edges, murmuring little charms. "Can you get rid of him?"

"Jace, this magic is very old and very powerful and what's worse the ceremony was interrupted so I have no idea how bonded you are."

"I assure you, Magnus, I have in no way 'bonded' with Sebastian."

Magnus shot him a sharp look and stood up. "Well I'm glad to see your personality hasn't been affected."

Jace forced a smile. "So what are you going to do?"

"I'm not letting you leave this room," the warlock said quietly. "It's too dangerous."

Jace's smile vanished. "You're going to leave me in _here_? You can't!"

Magnus turned to him, eyes steely. "What would you have me do, hm? Sebastian is too dangerous." He spat and Jace flinched at the raw fury he saw in Magnus' eyes because of Alec.

"Oh, god, _Alec_." Jace half-sobbed. "Is he here? Is he okay?"

Magnus nodded, "He's here," he looked away. "He'll...He'll _be _okay."

Jace wasn't sure what to say. There had been part of him that had thought-_hoped- _that night had been a bad dream. He closed his eyes briefly and all he could thinkhearfeel was Alec twisting away and begging and crying.

_Jace please, Jace stop!_

Here in the dark room, tied to the chair with the ropes biting into him he knew it was real.

When he opened his eyes he was only half surprised to feel tears burning his eyes. "He knows it wasn't me, right?" he asked, voice wavering.

Magnus sighed, "Yes, we told him."

"We?"

"Clary and Isabelle are here, they know too."

Jace nodded and took a deep breath, trying to steady himself. "How long will I be in here?"

"Hopefully not too long."

"Can I see Clary? Isabelle? Alec?"

"Not Alec," Magnus snapped but then his expression softened. "I'll ask about Clary and Isabelle. And I'll leave a light for you."

* * *

><p>Magnus shut the door with sigh and locked it. He didn't like having to lock Jace up, Jace didn't deserve it, but he couldn't risk Sebastian getting out again.<p>

He moved back through to the living room where the floor was strewn with ancient spell books and Isabelle and Clary were sprawled among them searching for anything to unbind Sebastian from Jace. Alec was still in the bedroom, Magnus had charmed him into a dreamless sleep.

"Is he okay?" Clary asked, looking up at him immediately. "Is he awake?" She looked awful; her face was pale, her nails were bitten and there were dark circles under her eyes.

"He's awake. He wants to see you and Izzy."

Clary jumped at the opportunity, "Yes! Of course I want to see him!"

But Izzy looked away. "I don't want to see him."

Clary looked at her, a mixture of anger and understanding. "Isabelle we need to support him." she said softly.

"I know Clary," Izzy said quietly. "But I don't know if I can look at him after what he-Sebastian-did to Alec."

Magnus ran a hand through his hair; this would be far trickier than simply removing Sebastian. Even after Jace was free he'd still be there, etched in their memories, in Alec's bad dreams. Magnus tried to imagine how it must feel to have your best friend, brother do something like that to you. How must Izzy and Clary feel knowing what Sebastian had been doing to Alec? Did they feel as guilty as he did? Had they analysed every interaction they had had with both of them to see what they had missed?

Magnus knew he should have realised something was wrong the minute Alec left him for Jace. Jace had never had any interest in his parabatai and he'd be so in love with Clary, Magnus should have known something was wrong.

He watched as Isabelle pressed a hand to her mouth, blinking away tears and Clary crossed the room and laid a comforting hand on her back. He glanced at the closed bedroom door and sighed.

How were they supposed to move past this?

"Any luck on finding anything?" he asked, trying to change the subject.

Isabelle shrugged and Clary shook her head before standing up, "I'm going to go and see him, okay?"

When Izzy nodded she left the room and Magnus crossed the room to sit beside her. "Are you okay?" he asked gently.

"No," she snapped. "My brother has been possessed by his brother and has been torturing and...and..." she broke off with a sob. "Magnus what am I supposed to _do_?"

Magnus put an arm around her and shook his head. "We'll get passed this." He said, but words tasted bitter in his mouth.

They sat there for a while until Magnus stood up, "I'm going to go check on Alec, will you be okay?"

Izzy nodded, biting her lip and picking up another ancient book.

When he got in to the bedroom he found Alec standing by the window, forehead pressed against the glass. His arms were wrapped protectively around himself, he was trembling slightly.

"Alexander?" Magnus asked carefully. "How are you feeling?"

Alec shifted slightly and Magnus noticed Alec's hands balled into fists. "Fine." He said flatly.

"Alec..." he said, approaching him. "Alec you need to talk to me. You need to deal with this."

"I'm fine, Magnus." But this time his voice shook.

Magnus laid a hand on Alec's shoulder and Alec flinched and stiffened against the touch. "It's okay," Magnus soothed. Eventually Alec relaxed and Magnus wrapped his arms loosely around the Shadowhunter.

He needed to get Alec passed this. He could see him fading, reverting back to who he'd been before all this, quiet, shy, angry at the whole world and desperately scared. Magnus held him tighter.

"Was it..." Alec asked in a voice barely more than a whisper. "Was it my fault, Magnus?"

Magnus spun Alec to face him and gripped him by the shoulders, "_No, _Alec. Don't you _ever _think that."

Alec's eyes filled with tears. "But I could've stopped him...I could have fought but I didn't! I _didn't _Magnus. I just...I just _let _him..." Alec's eyes were wide and he looked like he was crawling out of his skin.

"Oh, Alec," Magnus pulled Alec to his chest and held him there, whispering soft words of love and comfort.

* * *

><p>Jace had fallen asleep after Clary left, he wasn't a hundred percent sure how he'd managed to fall asleep whilst tied to a chair in a cold dungeon in a warlock's apartment but he had. And he'd actually managed to sleep pretty well. He'd dreamt about Clary and Alec and Isabelle before Sebastian when they just had his deranged father to defeat, happier times.<p>

He was awoken when the door swung open and light streamed in.

"Magnus, that you? If it is I demand sustenance." Jace called, blinking in the bright light as his stomach growled.

The figure in the doorway moved in to the room. It wasn't Magnus. "Alec..." Jace said in a strained voice. Inside his head he felt Sebastian rumble.

He was wearing a dark coloured hoodie, his hands stuffed in the pockets. His eyes were darting around the room, looking anywhere but Jace.

"Alec-Alec...I..." Jace stammered. His mind was churning through images of that night, playing them over and over on a loop like an awful horror movie. "You know it wasn't me, right?"

Alec nodded. "I knew..." he said quietly. "I think I always knew. _You _never felt that way for me, I knew it wasn't you..."

Jace wasn't sure what to say but he didn't have to worry about it for long because Alec turned and left without a backward glance leaving him once more alone in the dark.

_You just let him walk away?_ Came Sebastian's voice.

"No. _No_." Jace said. "Magnus said...You can't be here!"

Sebastian cackled, _I'm no demon, little brother. Your silly drawing might have slowed me down for a bit but I'm back now. Did you miss me?_

Jace closed his eyes as Sebastian slipped in to control.


	8. Angel Blood

**AN: **It's been so long. I'm so, _so _sorry. This is the second to last chapter. It's a bit cutty (you'll understand when you read it) and I rewrote it about a million times and I'm _still_ not happy, so don't hate me! Thanks a bunch for all the favs/reviews, you guys are _awesome._

Also. I have no doubt that Cassie has awesome evil plans lined up for us but I lack her creativity especially when I play with other people's toys, sorry.

Sorry about the shift to present tense in the Jace bits, I prefer it generally and I kind of want to see what style I do better, any comments are welcome :)

* * *

><p>Jace tries to move but he can't, tries to take control back, but he can't.<p>

Sebastian chuckles, "Struggle all you like, little brother. It's not going to work this time." He purrs.

There are rope burns on his-**(Our, Sebastian corrects)**-wrists and their head is pounding.

"_Your_ head," Sebastian says smugly. "_I_don't feel the pain."

Jace had given up long before Magnus had tried to help and Magnus had failed. There wasn't anyone else. Sebastian had won.

"I'm disappointed," Sebastian growls as they slip through New York."You're my brother, I expected more."

It's so ridiculous that Jace almost laughs and why shouldn't he? At present his parabatai hates him and with good reason and he's a glorified skin suit for a boy infused with demon blood at birth. "What are you doing Sebastian?" he asks.

There's a pause and then. "I don't really know."

This time Jace does laugh.

"Well I suppose you've already ruined my life _and _stolen my body, perhaps you deserve a rest."

Sebastian runs a hand through (their) hair lazily, "Or perhaps I could rally an army of Downworlders and attack Idris. Or I could continue systematically ruining your life."

"You won't hurt Clary," Jace says and he's not sure if it's a question or a statement.

"No, but there's always Isabelle..."

* * *

><p>"What do you mean he's gone?" Clary asked, for the hundredth time. Her whole body was trembling, <em>we've lost him again, I've lost him again.<em>

"He's gone Clary," Alec snapped. "Stop asking and just accept it. Sebastian took him, he's _gone._"

Clary glanced at him. He was leaning up against the wall, wearing a dark, baggy hoodie and dark jeans, there were bags under his eyes and he had his arms wrapped protectively around his chest. He looked more like the boy Clary had met when she'd first been to the institute than the boy who had kissed Magnus in front of everyone and sent Jace annoying postcards. He looked like he was barely holding himself together.

Magnus was sat on the couch, chin rested on his interlocked hands. Izzy was pacing, her usually perfect hair was messy from the amount of times she'd tugged at it in frustration. "They can't have gone far." She said, winding her whip around her wrist nervously.

Clary stood up, "Well let's go look then!"

"We don't know what Sebastian is going to do," Magnus said quietly, he glanced at Alec briefly. "It might be dangerous."

"What? So you just want us to wait here then?" Izzy stopped pacing and fixed him with her dark gaze. "Jace is my brother and I'm not about to let some _freak _walk off with his skin."

"Isabelle-" Magnus began but Clary cut him off.

"She's right and you know it, Magnus. Besides, we're Shadowhunters, danger is nothing new. We can get Simon to help and Luke and my mother and Jordan and Maia. If we explain what happened to them maybe they'll..." Clary said.

"If we tell them Jace is fused with Jonathon Morgenstern they'll kill him," Alec interrupted. _Sebastian, _Clary thought. _Jonathon is Jace's name. _She turned to look at Alec who was standing, head lowered and arms at his side, hands balled in to tight fists. He was trembling and though his dark hair covered his eyes Clary knew they were brimming with unshed tears.

"They'll say he's a danger to everyone. You know they will." He said. Izzy looked like she was about to argue but in the end she stayed silent so Alec continued: "They'd lock him up and try him with the Mortal Sword and he'll be found guilty of the attack on Idris, of murdering Shadowhunters, of helping Valentine. They won't care that he's using Jace's body, they'll just care about revenge."

"Luke wouldn't, neither would my mother or your parents," Clary said, enraged. "They wouldn't let any of that happen, Alec."

Alec laughed a brittle, broken sound. "Do you _really_ think they could stop them? If we tell them other Shadowhunters will find out and Jace will be killed and we'll all be punished for hiding it from them for so long."

Clary glanced pleadingly at Isabelle but she was standing pale faced and tight lipped, Magnus' gaze was fixed firmly on his shoes. "But he's _Jace. _I love him, I'm not about to give up on him. Alec, he's your parabatai, your brother, you _can't _just give up." She said eyes wide and begging.

Alec bit his lip. Clary turned again to Isabelle and then to Magnus and neither said a word. She couldn't believe that it was _Alec_ who had given up first. Alec, Jace's other half, his brother, his best friend. "Doesn't that mean anything to you?" she said weakly. "Don't you feel anything about him anymore?"

Then, in a flash, Alec moved. He leapt across the room and before Clary could register anything he had her by the throat. "Don't you _ever _presume that _you _care about him anymore than _I _do." He growled his eyes dark and terrifying.

"_Alec!"_ Isabelle cried, hand to her mouth.

Alec glanced at her and let Clary go. She crumpled to the ground, heart beating rabbit-fast, blood roaring in her ears. Alec had turned to face Magnus, "If we find him can he be saved?" he asked quietly.

Magnus blinked in surprise and for a few moments he stared blankly at Alec. "I don't know," he said eventually. "The spell that was used is ancient and very, _very_ powerful. Jace was resisting it before but now he's weaker, if Sebastian gains total control then there's nothing I can do."

Isabelle helped Clary up and then touched her brother lightly on the arm, Alec flinched slightly. "Do you feel anything, Alec?" she asked softly. "I mean you'd know if he was dead, you'd feel it, like you did in Idris..."

"He's not dead," Alec said quietly. "But he feels weak, so, _so_ weak."

"Then we have to find him fast," Clary said firmly, Alec turned to her and nodded.

Magnus stood up, "Call Simon and the werewolves but no one else, Alec's right, if the wrong people find out Jace will be in big trouble. I'll stay here and find something to break them apart, Alec you're staying too."

Alec didn't argue.

* * *

><p>"<em>They'll come for me," <em>Jace says.

Sebastian hums. "Oh, I don't doubt that, brother."

Jace falters. He's getting better at reading Sebastian's thoughts._"You want them to, why?"_

"Well, so I can destroy them of course!" he says in a cheery voice but to Jace it sounds hollow, empty. A lie.

"_You really don't know what to do, do you?"_ It's a realisation so sudden that Jace isn't sure how to react. Sebastian grumbles and Jace reaches out, testing, searching out his brother's thoughts. Maybe it's the angel blood coursing through the veins he's wearing or maybe Magnus' spell did something after all but what he finds isn't the bright hot fury and _need _to hurt that had scratched at the back of his skull. It's a dull, simmering burn now but there's desperation there and Jace knows from experience that desperation can be dangerous.

* * *

><p>"Do you really think he'll still be in New York?" Izzy asked quietly as they left Magnus's.<p>

_No,_ Clary thought. "Yeah, he can't have gone far like you said, Iz." She said.

* * *

><p>Jace can feel Sebastian's restlessness. He can feel Sebastian's <em>need <em>to do _something._ But Sebastian doesn't know what. They're sat on a roof, Jace isn't a hundred percent sure where but they're close enough to the institute that Jace can see the roof off in the distance.

"_We could leave." _Jace says quietly.

Sebastian huffs. "No. I still have people to hurt." It's half-hearted, unfilled.

Jace swallows, if he can convince Sebastian to leave New York they'll be safe. His family will be safe. It'll hurt, it'll hurt like hell but it's the best thing he can do. He knows they won't stop looking, knows Clary won't stop looking. Maybe they'll find him one day. _Maybe._

* * *

><p>Clary and Isabelle had just split up to search when her phone buzzed. For half a heart beat she hoped it would be Jace, it wasn't though. "Alec, what's up?"<p>

"Magnus has found something, Clary," his voice was strange but Clary was too overjoyed to think about that too much. "He called in an old favour; he thinks we can save him!"

* * *

><p>"<em>You don't want to. You can't hurt Clary, I know you won't." <em>Jace tries.

He feels Sebastian waver.

"_And you've hurt Isabelle enough because of..." _Jace still can't say it. _"Because of what you did to Alec. Who else is there to hurt but me, Sebastian?"_

* * *

><p>Clary spotted Jace just as she was beginning to think about giving up. He was sitting on a roof of an apartment building, gazing out over the city.<p>

She pulled out her phone and dialled a number as she broke in to a run. "Izzy," she said urgently when the call was picked up. "I've found him. Tell Magnus and meet me at the new Elysium Apartment building."

Clary had been walking all day, her feet ached, her head was pounding and her body was crying out for rest but that was all forgotten as she barrelled towards the building and pushed through the doors to the stairs.

Jace was there. Jace was safe.

She burst through the fire exit that led to the roof. "Jace!"

He turned to her. His eyes were dark, dark as Sebastian's, but they were flecked with Jace's gold colour. _Jace is still in there. _Immediately she drew the blade Isabelle had given her.

Sebastian smiled, "Now come on, little sister, you won't actually _use _that on me, will you?"

_He smiles like Jace. _The hand gripping the blade was shaky; she knew she couldn't hurt him. Jace was somewhere in there, she couldn't risk hurting Jace. She stood her ground. "I'll do whatever it takes to get Jace back."

Her brother chuckled and ran a hand through his-_Jace's_ hair. "And what exactly will hurting me do?" then he grinned, playing with the frayed edges of Jace's shirt calmly. "And what makes you so sure he's even still in here?"

"I know," she said quietly.

"Oh, of course, silly me. You _know._ Or was it Alexander that told you?" he said, watching for her reaction intently. "I imagine he must be a _mess _right now."

Clary thank God Isabelle hadn't been there to hear that and her grip tightened on the blade. "You deserve so much more than death for what you did to Alec and Max," she hissed.

"So I'm told," he grinned and stepped forwards. "But there's one little problem, sister; kill me and Jace dies too."

For a brief moment Clary thought Sebastian was about to attack her but when he didn't she noticed a slight weariness in the way he stood. He looked bored, uncomfortable, like he wanted nothing more than to be left alone and not to have to fight.

"You won't hurt me," she said cautiously.

He rolled his eyes. "And you won't hurt me. So what are we to do, little sister?"

Feeling bolder Clary stepped forwards. "Give Jace back."

Sebastian laughed again, "You make it sound like I have him hostage or something. You do realise he's somewhat _connected _to me?" But he stepped back.

"So leave his body," Clary growled.

"Yes, because that's a tempting possibility. Leave this body and die again, do you really want me dead, sister? Or maybe you'd prefer it if I was in there with _you._"

Clary brandished the knife. "Like I said, you deserve worse than death." Out of the corner of her eye she saw Izzy and Magnus and a dark haired woman hurrying across the road towards the building. She needed to keep Sebastian distracted, it was their only chance.

"What will you do if I don't?" Sebastian asked, sounding genuinely curious.

Clary didn't want to think about it. _Hurry, Magnus, _she thought. "You will." She said. "We'll find a way."

Sebastian advanced on her and before she could react he had her by the shoulders. "I won't let you." he hissed. Clary shook.

The door behind them burst open and suddenly Sebastian was thrown off her. Izzy had her whip tangled in his legs and the dark haired woman was helping her hold him down. "Clary, help us!" Izzy cried. Clary did as she was told and pinned down Sebastian's right arm.

The dark haired woman, who Clary vaguely recognised from the party in Idris, nodded and turned to Magnus. "Now!" she barked.

Magnus' hands were glowing green-blue with magic he knelt and laid them on Sebastian's chest crying out words that dripped with magic and made Clary's hair stand on end. The green-blue light from Magnus' hands spread through Sebastian's body.

Sebastian _screamed._

Clary closed her eyes.

* * *

><p>When it was all over and the light had receded Magnus was panting and slumped and Jace's body was still.<p>

"Did it work?" Izzy asked in a hushed voice.

"Don't know," Magnus croaked in a raw voice.

The dark haired woman helped him up and when he swayed she supported him. "We have to wait until he wakes up."

"You two will have to carry him back to mine," Magnus said with a small grin.

Clary stood shakily, still blinking after the bright light. She and Izzy bent and heaved Jace's dead weight up between them. Together they struggled back to Magnus' where Alec was waiting for them. Clary tried not to notice how he couldn't even look at Jace let alone help them get him on to the bed.

"Now all we can do is wait," the dark haired woman, Tessa, said.

"I'm going to check on Magnus," Alec muttered, Magnus had collapsed on to the couch as soon as they had gotten in.

"I'm starved," Isabelle announced as her brother left. "Want anything, Clary? Tessa?" Clary shook her head but she noticed Isabelle was staring at Tessa distrustfully. Neither of them had any idea what Magnus had done but it was far more powerful than anything they'd seen him do previously.

Tessa took the hint, "Yes, I could do with some tea or coffee, I'll come with you, Isabelle."

When Clary was alone she finally allowed herself to stroke Jace's hair and sob. "Please be you, _please._"

* * *

><p>Clary awoke pillowed on a familiar chest.<p>

The room was pitch black, the curtains drawn. Someone had draped a blanket over her.

The body beneath her stirred.

She sprung away and found herself staring in to golden eyes.

"Clary?" Jace said.


	9. Fall Out

**AN: **thank you guys so much for all the reviews, favs and alerts, you've been awesome but alas this is the final chapter, more of an epilogue really. I do have some ideas for other TMI fics, one is a Hunger Games AU but I won't be writing any for a while since I want to focus on my daemon!AU.

Sorry, it's pretty short but I hope you guys don't mind but all is said and done :)

* * *

><p>"Can't sleep again?"<p>

It was 3am. Jace was sitting in the Institute greenhouse watching some night-time flowers bloom. He turned to find Izzy leaning against the door frame, dressed in pyjamas and pink fluffy slippers, dark hair captured in a loose pony tail.

"Sleep is for the weak," he shrugged and Izzy smiled sympathetically. She knew he meant, _I'm terrified Sebastian will come back._

"It'll be okay," Clary had said when Jace had woken up free of Sebastian."It'll be okay, Jace. It'll all be okay now."

Jace had wanted to hit her. To scream at her because how could it ever be _okay_? Jace couldn't close his eyes without seeing what Sebastian had done to Alec. Alec wouldn't let anyone touch him, still had nightmares, wasn't eating right, wouldn't even _look _at parabatai hated him and for good reason. How could that ever be okay?

He had tried to apologise but how are you supposed to apologise for _that_?

"Alec, Alec, I'm so sorry I-" but Alec had cut him off, eyes firmly locked on the ground.

"It's fine." He'd said, before leaving. Alec was staying at Magnus', he hadn't been home in a week.

Clary had held his hand as Magnus explained that Sebastian wasn't gone; the spell was too powerful for that, he was merely dormant. Trapped in the darkest corners of Jace's mind. When Jace slept he sometimes thought he could hear Sebastian moving around, scratching at whatever mental chains Magnus had put him in, so Jace stopped sleeping.

Izzy was the only one he could talk to about what happened. Clary refused to, she said it might bring Sebastian back, that it was over, that they should pretend it never happened.

"What do you think would have happened if Clary hadn't found you?" Izzy asked as she sat down next to him.

Jace sighed. "I really don't know, Iz." He remembered Sebastian's uncertainty, his seeming reluctance to hurt anyone else. "I was trying to get him to leave," Jace said eventually. "To leave New York so he wouldn't hurt anyone else."

Izzy frowned, "Do you really think he would have?"

"I don't know. He was just...really; he didn't know what he was going to do."

Izzy watched him for a long time. "Maybe it was a two way thing. He got control of your body but that meant he got influenced by you too."

Jace drew his knees up to his chest and leant his head on them. "What happens now, Izzy?" he asked quietly. "How am I supposed to make this okay?"

He knew she'd know what he was talking about. "Alec will get over it, even if it takes years, Jace. You know he will." She reached out and put an arm around his shoulders. "What about you?"she asked softly.

"He's still there, Iz." Jace whispered. "I can feel him. I can't hear him or anything but I can feel him." It felt like a shadow, a phantom weight."What if he comes back?"

If he had said that to anyone else they would have assured him that it would never happen. Not Izzy.

"Then we'll deal with it," Izzy said. "We'll find a better spell, a stronger spell." She smiled softly. "Jace, no matter how bad it gets it'll get better; you of all people should know that. It might take years but we'll get there."

* * *

><p>They were in the weapons room three months after The Incident when Alec touched his arm and looked him in the eye.<p>

That was when Jace started to believe that it would be okay.


End file.
